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Nimfa-mama [501]
3 years ago
9

g What is the final velocity of a hoop that rolls without slipping down a 6.92 m high hill, starting from rest

Physics
1 answer:
liberstina [14]3 years ago
5 0

Answer:

The value is  v  = 8.24 \  m/s

Explanation:

From the question we are told that

  The height of the hill is  h =  6.92 \  m

Generally from the law of energy conservation we have that

   PE =  KE +  RKE

Here  PE is the potential energy of the hoop which is mathematically represented as

       PE =  mgh

 KE is the kinetic energy of the hoop  which is mathematically represented as

     KE =  \frac{1}{2}  * m * v^2

And  

  RKE  is the rotational  kinetic energy which is mathematically represented as

      RKE  =  \frac{1}{2}  * I  *  w^2

Here I  is the moment of inertia of the hoop which is mathematically represented as

           I  =   m *  r^2

and  w  is the angular velocity which is mathematically represented as

          w =  \frac{v}{r}

So

         RKE  =  \frac{1}{2}  * m r^2    *  \frac{v}{r} ^2

=>     RKE  =  \frac{1}{2}  * m r    * v^2

So

     mgh =   \frac{1}{2}  * m * v^2 +   \frac{1}{2}  * m r    * v^2

=>   v  =  \sqrt{gh}

=>   v  =  \sqrt{9.8 *  6.92 }

=>   v  = 8.24 \  m/s

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Answer:

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Answer:

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Explanation:

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